Ring stretcher and expander



June 26, 1951 w, ROTHENBERG 2,558,271

RING STRETCHER AND EXPANDER Filed June 6, 1949 2 Sheets-Sheet 1 INVENTOR. w M06 40. EOTHENBEPG June 26, 1951 M. w. ROTHENBERG RING STRETCHER AND EXPANDER 2 Sheets-Sheet 2 Filed June 6, 1949 8 MW 2 m5 mm mm m .%M 5 E WY B.

Patented June 26, 1951 2,558,271 RIN G STRETCHER AND EXPANDER Moe W. Rothenberg,

Los Angcles, Calif., assignor to Barney H. Wenner, Los Angeles, Calif. Application June 6, 1949, Serial No. 97,419

1 Claim. 1

The present invention relates to an improved ring stretcher and expander particularly useful as a tool for jewelers in adjusting the size of rings to fit individual fingers.

An object of the present invention is to provide an improved ring stretcher and expander which is relatively small and of a minimum number of parts which may be manufactured and assembled to produce an economical unit, and one which may be easily and conveniently operated for its intended purpose.

Another object of the present invention is to provide an improved ring sizer especially adapted to alter rings to desired sizes accurately and with a minimum amount of efiort on the user of the device.

A further object of the present invention is to provide an improved ring sizing machine of the character described herein, which may be produced inexpensively in accordance with present day mass production methods and techniques.

The features of the present invention which are believed to be novel are set forth with particularity in the appended claim. This invention itself, both as to its organization and manner of operation, together with further objects and advantages thereof, may be best understood by reference to the 'following description taken in connection with the accompanying drawings in which:

Figure 1 is a view in side elevation of an improved ring sizing machine embodying features of the present invention,

Figure 2 is a view in end elevation taken substantially in the direction indicated by the arrows 2-2 in Figure 1, but with the operating crank in a different position for contracting the size of the ring in Figure 2 instead of being in position for stretching the ring as shown in Figure 1,

Figure 3 is a sectional view taken substantially on the line 33 of Figure 2,

Figure 4 is a sectional view taken substantially on the line 4-4 of Figure 1,

Figure 5 is a view taken substantially on the line 5-5 of Figure 2,

Figure 6 is a perspective view of the mandril of the machine shown in Figure 1, and

Figure '7 is a perspective view of the end of the mandril shown in Figure 6 separated from the cooperating locking bushing with a dowel pin therein for locking cooperation with the slot shown in the end of the mandril.

The ring sizing machine is intended to either expand or contract the size of a ring of the type worn by individuals, as occasion demands, to fit precisely the size of individual fingers.

A single crank or craftsmans wrench I5 is selectively placed in either the square opening of the rotatable nut 5 and turned to expand a ring initially placed on the mandril 2; or the same wrenchv I5 may be placed into the similarly cooperating square opening in the nut 5A and turned to move the punch 1 downwardly to squeeze a ring initially placed in the appropriately sized aperture in the adjustably positioned sizing block 4, thereby to contract the ring placed between such punch 1 and the sizing block 4.

Specifically, all of the operating components are mounted in a single unitary housing I, which may comprise a forging or casting so shaped as to provide a generally rectangularly shaped supporting base IA and a pair of cylinders IB, IC extending respectively with their axes perpendicular to one another, to house respectively the ring stretching operating mechanism and the ring contracting mechanism.

Referring to the ring stretching mechanism shown in Figure 3, it is noted that the internally threaded nut 5 is rotatably mounted in the cylindrical housing IB with limited movement along its axial direction, such axial movement being prevented, on the one hand, by the retaining ring 8 threaded into the cylindrical housing IB and, on the other hand, by the bushing 6 prevented from rotating in the housing I B by the headless set screw l4 threaded both in thehousing IB and the bushing 6. p

The nut 5 has a centrally disposed square aperture adapted'to receive the square shank ISA of the wrench l5, whereby the nut 5 may be turned by such wrench I5. The nut 5 is internally threaded and cooperates with the threaded shoulder 3A of the expander 3. The expander 3 comprises a rod tapered at its left-hand end in Figure 3 with a number one Morse taper of approximately six-tenths of an inch per foot, so as to expand the encompassing split mandril 2 as the expander 3 is moved to the left in Figure 3- upon turning of the wrench l5 and connected nut 5. For this purpose the expander 3 is prevented from rotating with the nut 5 by a Woodrufi key l3 entering a cooperating slotted portion of the expander 3 and the bushing 6, it being noted again that the bushing 6 is secured to the cylindrical housing IB by the set screw I4. The mandril 2 is also prevented from rotating by securing it against rotational movement of the bushing 6, the means provided beingthe dowel pin I 2 having one of its ends entering a cooperating opening in the bushing 6 and the other one of its ends entering the groove 2A in the mandril 2.

The mandril 2, as perhaps best shown in Figure 6, comprises a tapered sleeve with an annular shoulder 23 thereon at its larger end for disposition between the internal annular flange of housing IB and the adjacent surface of the bushing 6, the shoulder 2B thus serving to mount the mandril with respect to the housing IB.

It is noted further that the mandril 2, in order to give the expansible properties, has its walls slit longitudinally along its length, there being provided, in general, two series of slits alternatively arranged, The slits 2E of one series extend all the way through the shoulder 2B but terminate short of the left-hand end in Figure 6, or the smaller end, while the slits 2F of the other series extend all the way through to the lefthand end, or smaller end, of the mandril 2 but extend only a limited distance within the shoulder 23. Thus, there is provided a mandril having alternatively arranged longitudinal slots, with the slots of one series terminating short of opposite ends of the mandril, whereby the mandril may be easily expanded radially outwardly when and as the tapered expander 3 is moved to the left in Figure 3.

With respect to the ring contracting mechanism shown in Figure 4, the cylindrical housing portion i is substantially the same size as the cylindrical portion IB shown in Figure 3, and is adapted to receive a nut 5A and a retaining nut 8A of identical size as the corresponding nut 5 and retaining nut 8 in Figure 3. The nut 5A is prevented from moving in its axial direction by the shoulder thereof engaging, on the one hand, the retaining nut 8A and, on the other hand, the adjacent shoulder of the housing It). The internally threaded nut 5A cooperatively receives the threaded shank of the punch 1, so as to move them vertically when and as the nut 5A is turned by the crank I5 which is inserted in the nut 5A for that purpose. In order to prevent rotational movement of the punch I, so as to make the motion of the punch 1 substantially only translational, there is provided a similar Woodruff key 13A recessed, on the one hand, in a groove in the punch I and, on the other hand, in a cooperating groove in the housing 1C. This punch 1 may thus be moved downwardly into cooperation with a ring initially inserted into one of the tapered apertures 4A in the sizing ring 4.

The sizing ring 4 is rotatably mounted in adjusted position on the base iA about the axis of the post 9, having a shank threaded into the base IA. The sizing ring 4 is slipped over this post 9 and may be conveniently removed therefrom so as to dispose either side of the ring 6 upwardly, as desired, it being noted that tapered apertures 4A on opposite sides of the sizing ring 4 are all of different sizes and total twelve in number. Any one of these twelve sizing apertures 4A may thus be positioned directly under the punch I, so that a ring may be wedged therein to decrease its efiective diameter upon rotation of the inserted wrench I5.

While the particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects and, therefore, the aim in the appended claim is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

In a ring sizing machine of the character described, a housing adapted to rotatably support a nut, a retaining ring releasably mounted on said housing and preventing axial movement of said nut, a tapered expanding pin having a threaded shoulder thereon for cooperative engagement with the threads on said nut, a bushing within said housing, a set screw securing said bushing to said housing, releasable locking means between said bushing and said tapered expanding pin, an expansible mandril mounted on said tapered pin and having a shoulder thereon disposed between a shoulder on said housing and said bushing, and releasable locking means between the bushing and said shoulder, said mandril having a pair of alternate series of longitudinally extending slots therein with slots of one series terminating short of opposite ends of said mandril.

- MOE W. ROTHENBERG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 72,410 Mason Dec. 17, 1867 201,654 Davies Mar. 26, 1878 516,180 Bernhardt Mar. 13, 1894 1,830,235 Mazer Nov. 3, 1931 1,898,586 Mazer Feb. 21, 1933 

